Method count

dialect/sql/sqlgraph/graph.go:1032–1064

(ctx context.Context, drv dialect.Driver)

}

func (q *query) count(ctx context.Context, drv dialect.Driver) (int, error) {
	rows := &sql.Rows{}
	selector, err := q.selector(ctx)
	if err != nil {
		return 0, err
	}
	// Remove any ORDER BY clauses present in the COUNT query as
	// they are not allowed in some databases, such as PostgreSQL.
	if q.Order != nil {
		selector.ClearOrder()
	}
	// If no columns were selected in count,
	// the default selection is by node ids.
	columns := q.Node.Columns
	if len(columns) == 0 && q.Node.ID != nil {
		columns = append(columns, q.Node.ID.Column)
	}
	for i, c := range columns {
		columns[i] = selector.C(c)
	}
	if q.Unique {
		selector.SetDistinct(false)
		selector.Count(sql.Distinct(columns...))
	} else {
		selector.Count(columns...)
	}
	query, args := selector.Query()
	if err := drv.Query(ctx, query, args, rows); err != nil {
		return 0, err
	}
	defer rows.Close()
	return sql.ScanInt(rows)
}

func (q *query) selector(ctx context.Context) (*sql.Selector, error) {
	selector := q.builder.